Air exhaust system for waste material

ABSTRACT

An exhaust system for removing relatively stiff waste strips of paper cut from a thick document or booklet by a continuous cutting wheel. Air under pressure is injected into a discharge tube near the cutting wheel to draw the waste strips into the tube and convey them through the tube to a point of discharge. The discharge tube is oriented in the direction of movement of the document to minimize jamming because of the stiffness of the waste strips being handled.

I United States Patent 1191 1111 3,827,320 Parks Aug. 6, 1974 AIR EXHAUST SYSTEM FOR WASTE 3,465,625 9/1969 Daly 3/100 MATERIAL 3,570,339 3/1971 Vandersip.... 83/100 X 3,683,732 8/1972 Juppet 83/100 [75] Inventor: James D. Parks, Iowa Clty, Iowa Assignee; Westinghouse Learning Primary Examiner-Willie Abercrombie Corporation, Iowa City, Iowa Attorney, Agent, or Firm-James C. Nemmers [22] Filed: Feb. 16, 1973 [57] ABSTRACT v [21] Appl- No; 332,813 An exhaust system for removing relatively stiff waste strips of paper cut from a thick document or booklet 52 US. Cl. 83/100 by a Continuous cutting wheel- Air under pressure is 51 1111. c1 B26d 7/06 injected into a discharge tube hear the Cutting Wheel [58] Field 61 Search 83/100 to draw the Waste Strips into the tube and convey them through the tube to a point of discharge. The dis- [56] References Cited charge tube is oriented in the direction of movement UNITED STATES PATENTS of the document to minimize jamming because of the stiffness of the waste strips being handled. 2,722,983 11/1955 Gibson et al 83/100 x 3,144,216 8/1964 Billingsley 83/100 x 7 Clalms, 4 Drawmg Flgures AIR EXHAUST SYSTEM FOR WASTE MATERIAL BACKGROUND OF THE INVENTION The invention relates to improvements in means for disposing of waste strips cut from documents, particularly thick documents or booklets, that are moving successively at a high speed through a cutting station.

There are a number of applications where the edge or edges of paper or other similar material are trimmed while the material is moving at a relatively high rate of speed. For example, where the answers to tests, surveys, etc., are made on sheets bound into a booklet, and the answers are to be machine read, it becomes necessary to separate the papers of the booklet into individual documents or sheets. If the booklet is properly designed, this can be done easily by running each booklet through an apparatus containing a pair of cutting wheels or blades that will trim or cut the bound edge of the booklet while the booklet moves through the apparatus. This, of course, separates the papers into individual sheets which can be collected in a suitable hopper. However, the waste edge of the booklet must also be separated from the sheets so that it can be disposed of in a proper manner. Means must therefore be provided to convey this waste strip away from the separated sheets of the booklet into a selected location for proper disposal.

The prior art does disclose air exhaust or vacuum systems which will pick up and convey waste strips in some instances. An example of such an apparatus is shown in US. Pat. No. 3,465,625. However, where the waste strip is relatively thick and therefore somewhat stiff, the systems of the prior art will not work since the strips are difficult to convey and will readily jam the apparatus. If jams occur, particularly at the high speeds at which booklet slitting apparatus are operated, the waste strips can create time consuming jams and can also cause damage to the separated sheets which when subsequently passed through machine readers may cause a jam in that machine.

It is, therefore, an object of the invention to provide an apparatus for disposing of relatively thick, stiff waste material which has been cut from successive booklets moving at a high speed.

It is a further object of the invention to provide such an improved appartus which is simple, trouble and jam free, easy to maintain and low in cost.

SUMMARY OF THE INVENTION The invention is for a booklet slitting apparatus having a waste discharge tube oriented in the direction of movement of the booklet with the inlet end of the tube located immediately downstream from the cutting wheels. An air tube and nozzle arrangement extends slightly into the inlet end of the exhaust tube so that air under pressure can be injected at the point of entry of the waste strip. This creates a vacuum upstream from the exhaust tube near the cutting wheels so that the waste material is drawn into the tube and conveyed in an air stream to the desired point of discharge.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a booklet slitting apparatus and showing the waste exhaust system of the invention;

FIG. 2 is an enlarged perspective view looking upstream and showing the waste exhaust tube and its position relative to the cutting wheels;

FIG. 3 is an enlarged perspective view of a portion of FIG. 2 with part of the inlet end of the exhaust tube broken away to show the air injection means; and

FIG. 4 is a perspective view looking downstream and showing a portion of the booklet slitting apparatus with the cutting blades removed so as to show the air exhaust tube and ramp of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION Referring first to FIG. 1, there is illustrated a booklet slitting apparatus of a known design which apparatus includes an input hopper 10 where the booklets to be trimmed are stacked and individually fed by drive wheels 12 into the cutting station indicated generally by the reference numeral 14. In the cutting station 14 there are a plurality of pairs of positive drive wheels 16 which convey individual booklets at a high speed across the table 18. A vertical sidewall 20 serves as a guide against which the side edge of each booklet moves so that the booklets are in proper alignment when they are passed between the upper cutting blade or wheel 22 and a lower cutting wheel 24 that extends upwardly through opening 25 in table 18. The cutting wheels 22 and 24 are mounted as shown in FIG. 1 so that their cutting edges are in alignment and are spaced from the vertical sidewall 20 a distance equal to the thickness of the bound edge that is to be trimmed from each booklet in order to separate the individual pages. When the trim or waste edge strip is completely out from a booklet, the individual pages are conveyed into and stacked in an output hopper 26. The specific way in which the drive wheels 12 and 16 and the cutting wheels 22 and 24 are driven is well known to those skilled in the art and does not form a part of the invention. Likewise, the particular design and operation of the input hopper l0 and the output hopper 26 form no part of the invention, and as is well known to those skilled in the art, the hoppers provide a method by which a stack of booklets can be stored in the input hopper 10 and individually fed in rapid succession to the cutting station 14 where the individual separated sheets are stacked in the output hopper 26.

Located partially in the cutting station 18 and extending across and through the output hopper 26 is the waste edge exhaust means indicated generally by the reference numeral 28. As best seen in FIGS. 2, 3 and 4, the exhaust means 28 includes an enclosed elongated exhaust tube 30 which extends in the direction of movement of the booklets through the cutting station 18. In other words, the exhaust tube 30 extends generally parallel to the sidewall 20. The exhaust tube 30 has its inlet end 32 located at a point just downstream from the point of engagement of the upper and lower cutting blades 22 and 24, and an inclined entry ramp 34 extends from this point of engagement to the inlet end 32. The tube 30 terminates in a discharge end 36 which is located in any desired place preferably beyond the output hopper 26 so that the waste strip discharge from the tube 30 will be discharged out and away from the separated sheets that are collected and stacked in the output hopper 26.

Extending into the inlet end 32 of tube 30 is the discharge end of a nozzle 38. Extending through the nozzle 38 from the discharge end 38 is an air passageway 40 that is connected through a tube 42 to a source of air supply (not shown). The air passageway 40 discharges air from the source of supply at a relatively high velocity and at a point inside the tube 30 beyond the inlet end 32 of tube 30. Thus, as pressurized air from the source of supply is passed through nozzle 38 and discharged into the tube 30 it will be discharged at the point A indicated in FIG. 3. This creates a slight vacuum upstream from the inlet end 32 of tube 30 around the area where the cutter blades 22 and 24 have started to separate the trim or waste strip from the booklet. This vacuum area or pocket in the cutting area draws and guides the waste strip into the inlet end 32 of tube 30. The entry ramp 34 assists in guiding the waste strip into the tube 30 and prevents the strip from being misdirected through the opening 25 and thereby causing a jam. The combination of the ramp 34 and the vacuum pocket created by the air discharge from nozzle 38 assures that the waste trim strip finds its way into the tube 30. Once the waste strip has entered the inlet end 32 of tube 30, movement of the booklet will carry the entire strip into the tube 30 until complete separation of the strip from the booklet at which time the positive air pressure and air velocity within tube 30 will convey the waste strip through the tube 30 and out the discharge end 36.

Thus, with the apparatus of the invention, the thick, relatively rigid and sticklike trim strips will be positively guided into the exhaust tube 30 and easily conveyed to the desired place without jamming the apparatus. Because of the design of the air exhaust system which provides for the creation of a vacuum pocket around the cutting area, air flow through the unit is not critical except that a sufficient volume of air must be provided to convey the relatively heavy, thick strips once they are completely separated from the booklet. Conveying of a strip is of course assisted by the momentum imparted to it by movement of the booklet itself by the drive wheels 16. With the system of the invention, the air does not have to be in any way coordinated with the speed of the drive wheels 12 and 16, and if an extremely high volume or velocity of air is used this will in no way interfere with the efficient operation of the air exhaust system. With an air exhaust system designed according to the principles of the invention, waste trim strips have been cut from booklets containing as many as 24 sheets. The thickness and width of the strips is limited only by the interior dimensions of the exhaust tube 30. Waste material of different lengths can be easily handled, although normally the booklets are approximately I 1 inches in length. An air exhaust system employing the principles of the invention can handle thick waste strips from booklets traveling successively at high speeds, whereas prior art apparatus would handle only single thickness continuous strips.

Obviously, the cost of adding such an air exhaust system to a booklet slitter is relatively small. There are very few parts all of which can be easily and inexpensively manufactured. Scine there are no moving parts, the system is maintenance free. Because of the vacuum pocket created by the design of the system, jams are virtually eliminated. Also, all other waste and dust produced by the cutting process is eliminated and discharged through the exhaust tube 30.

Although, I have described my invention only in connection with a preferred embodiment thereof, it will be obvious to those skilled in the art that various revisions and modifications can be made in the specific embodiment shown without departing from the spirit and scope of the invention. It is my intention that all such revisions and modifications, as are obvious to those skilled in the art, will be included within the scope of the following claims.

I claim:

l. In an apparatus for cutting strips from the side edge of booklets and the like that are being conveyed successively at a high rate of speed through a cutting station having a pair of rotating cutting wheels, an air exhaust system for disposing of the strips cut from said booklets, said system comprising an air exhaust tube extending generally in the direction of movement of said booklets through said cutting station, said exhaust tube having an inlet end and a discharge end with a substantially straight passageway extending between said inlet end and said discharge end, said inlet end being located downstream from and close to said cutting wheels, and means for injecting air under pressure into said passageway to create a slight vacuum upstream from said inlet end.

2. In the apparatus of claim 1 wherein said means includes a nozzle having a discharge opening positioned in said passageway just beyond said inlet end.

3. In the apparatus of claim 1 wherein guide means is provided between the inlet end of said tube and said cutting wheels to assist a waste strip in entering said inlet end.

4. An apparatus for cutting strips from the side edge of booklets and the like which have a plurality of sheets bound together along one edge, said apparatus comprising an input hopper for storing a plurality of said booklets, an output hopper spaced from said input hopper, a cutting station located between said input hopper and said output hopper, means for conveying individual booklets successively from said input hopper through said cutting station and into said output hopper, a pair of cutting wheels rotatably mounted in said cutting station, means for guiding said booklets along a straight path through said cutting station, said cutting blades being located along the path of movement of a booklet through said cutting station so as to trim the bound edge from said booklet as it passes through said station, an exhaust tube having an inlet end and a discharge end with a substantially straight passageway between said ends, said tube extending in the direction of movement of said booklets through said cutting station with said inlet end located downstream from and close to said cutting wheels, and means for injecting air under pressure into said passageway at a point just beyond said inlet end.

5. The apparatus of claim 4 in which said last mentioned means includes a nozzle having a discharge opening positioned in said passageway slightly downstream from said inlet end.

6. The apparatus of claim 4 in which there is provided means to guide the waste strip from said cutting wheels into said inlet end.

7. The apparatus of claim 6 in which said guide means includes an inclined ramp extending from said cutting wheels to said inlet end. 

1. In an apparatus for cutting strips from the side edge of booklets and the like that are being conveyed successively at a high rate of speed through a cutting station having a pair of rotating cutting wheels, an air exhaust system for disposing of the strips cut from said booklets, said system comprising an air exhaust tube extending generally in the direction of movement of said booklets through said cutting station, said exhaust tube having an inlet end and a discharge end with a substantiaLly straight passageway extending between said inlet end and said discharge end, said inlet end being located downstream from and close to said cutting wheels, and means for injecting air under pressure into said passageway to create a slight vacuum upstream from said inlet end.
 2. In the apparatus of claim 1 wherein said means includes a nozzle having a discharge opening positioned in said passageway just beyond said inlet end.
 3. In the apparatus of claim 1 wherein guide means is provided between the inlet end of said tube and said cutting wheels to assist a waste strip in entering said inlet end.
 4. An apparatus for cutting strips from the side edge of booklets and the like which have a plurality of sheets bound together along one edge, said apparatus comprising an input hopper for storing a plurality of said booklets, an output hopper spaced from said input hopper, a cutting station located between said input hopper and said output hopper, means for conveying individual booklets successively from said input hopper through said cutting station and into said output hopper, a pair of cutting wheels rotatably mounted in said cutting station, means for guiding said booklets along a straight path through said cutting station, said cutting blades being located along the path of movement of a booklet through said cutting station so as to trim the bound edge from said booklet as it passes through said station, an exhaust tube having an inlet end and a discharge end with a substantially straight passageway between said ends, said tube extending in the direction of movement of said booklets through said cutting station with said inlet end located downstream from and close to said cutting wheels, and means for injecting air under pressure into said passageway at a point just beyond said inlet end.
 5. The apparatus of claim 4 in which said last mentioned means includes a nozzle having a discharge opening positioned in said passageway slightly downstream from said inlet end.
 6. The apparatus of claim 4 in which there is provided means to guide the waste strip from said cutting wheels into said inlet end.
 7. The apparatus of claim 6 in which said guide means includes an inclined ramp extending from said cutting wheels to said inlet end. 